1. Field
This disclosure generally relates to techniques for monitoring computer systems. More specifically, this disclosure relates to a method and an apparatus that characterizes a computer system parameter by analyzing a target electromagnetic signal radiating from the computer system.
2. Related Art
Electromagnetic signals which radiate from computer systems can be used to characterize parameters of the computer system, including parameters that relate to components in the computer system. However, due to the potentially large number of sources of electromagnetic radiation that may be in proximity to the computer system (including electrical equipment, other computer systems, and even other components in the computer system of interest), there may be a substantial background of electromagnetic radiation that can mask the desired signal.
Typically, in order to maximize the desired signal against this background noise, an antenna is placed as close as is practicable to the source of the desired electromagnetic signal, often so that the antenna is inside the computer system of interest. However, for computer systems that do not have built-in antennas, inserting an antenna into an operating computer system can be time-consuming and risky, and powering down the computer system may not be practical or convenient. Furthermore, in some situations, the computer system of interest may not be easily accessible.
Hence, what is needed is a method and an apparatus that characterizes a computer system parameter by analyzing a target electromagnetic signal radiating from the computer system without the above-described problems.